The head of the International Atomic Energy Agency is in Iran to visit nuclear facilities the United States suspects could be part of a program for developing nuclear weapons.

The director-general of the Vienna-based International Atomic Energy Agency, Mohamed ElBaradei, is in Iran with a small team of technical experts.

Melissa Fleming, the agency's spokeswoman, says the purpose of their visit is to determine the precise nature of new nuclear facilities in central Iran.

"There are going to be talks, at the highest level, also with President Khatami and they're going to visit the two new sites that are under construction, and that have been kind of controversial," she said.

The Bush administration believes the construction, spotted on reconnaissance satellite photographs, could be used as part of a banned program to build nuclear weapons. Tehran has told the IAEA that Iran has no hidden atomic facilities and that all its nuclear activities are "non-military." President Mohammad Khatami said a month ago that Iran had discovered uranium deposits and had started mining.

Ms. Fleming says Iran informed the agency in September that it had ambitious plans to pursue a full nuclear fuel cycle from the mine to the waste to achieve independence.

An exile Iranian opposition group claims the republic is concealing sensitive equipment from the IAEA.

Iran is a signatory to the Nuclear Non-proliferation Treaty. The IAEA wants Iran to sign the so-called Additional Protocol to open the country up to inspections similar to those currently underway in Iraq.